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High-dose treatment with vitamin A analogues and risk of fractures
Peter Vestergaard1, Lars Rejnmark, Leif Mosekilde
1The Osteoporosis Clinic, Aarhus Amtssygehus, Tage Hansens Gade 2, DK-8000 Aarhus C, Denmark. p-vest@post4.tele.dk
Objective:
To study fracture risk associated with use of systemic vitamin A analogue (isotretinoin and acitretin) treatment.
Design:
Case-control study.
Setting:
Nationwide registry.
Participants:
A total of 124 655 patients with fractures (cases) and 373 962 age- and sex-matched controls. Main Outcome Measure Incidence of fractures in patients with and without exposure to systemic vitamin A analogues. Confounder control was performed for social variables, contacts with hospitals and general practitioners, alcoholism, and a number of other variables known to potentially affect fracture risk, including use of systemic, intramuscular, and topical corticosteroids and antiepileptic drugs and comorbid conditions.
Results:
No trend in risk of any fracture or of hip, forearm, or spine fractures was present with increasing doses or durations of treatment with vitamin A analogues. Subdividing vitamin A analogues into isotretinoin and acitretin did not change the results.
Conclusion:
Risk of fracture is not associated with vitamin A analogue treatment.
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